Surface mount technology has been adopted to aid in the interconnection of components to printed circuit boards wherein the components and the conductive traces of boards are miniaturized on closely spaced centers. The conductive leads of such components, including integrated circuits, discrete components, connectors and the like, are all arranged to reside in a common plane and rest upon the surface of printed circuit boards, upon the conductive traces thereon with solder, in some form, applied with appropriate flux to either the traces of the board or the contacts themselves. Thereafter, radiation in the form of infrared or laser beam energy, or other means of applying heat, is utilized to reflow the solder to join the various leads and traces together. In such applications, it is important that the leads and traces be precisely aligned to effect a solder interconnection between lead and trace without intermittent opens or bridging of solder to adjacent leads and traces to cause short circuits. A number of components, including connectors of the type shown in Japanese Patent Publication 279581/89 features housings having guide grooves along the bottom edge, or, alternatively, holes in the housings through which tail portions of contacts are fitted and held to be in alignment with the solder traces of a board. Typically, such connectors also include mounting hardware that clamps the connector housing in a precise position on a printed circuit board. With such techniques, contacts can be surface soldered to boards, although, as the contact spacing becomes smaller and smaller, including 1.27 mm or smaller, the fineness required of the plastic housing, channels and holes, makes the housings expensive due to the fine tolerancing in molding required. Additionally, the housing material utilized to define channels and holes may obscure the solder joint resulting to create an obstacle for inspecting the solder joint either visually or automatically, using image processing techniques as a part of quality control.
Accordingly, it is an object of the present invention to provide an improved surface mount electrical connector for soldering the closely spaced contacts of the connector to closely spaced traces on a printed circuit board. It is a further object to provide an improved surface mount connector of the solder type which facilitates the soldering of closely spaced contacts to printed circuit boards and allows a better inspection of the solder joints following the soldering operation.